Boeing Describes Two-Step KC-46 Tanker Certification Process

A model of the KC-46A stands above Boeing’s commercial 767 final assembly line in Everett, Washington, where the tanker will be built initially. (Photo: Bill Carey)

Boeing will seek two separate certifications from the U.S. Federal Aviation Administration (FAA) for its new KC-46A tanker, the commercial 767 derivative it is developing for the U.S. Air Force (USAF). The manufacturer will first apply for an amended type certificate from the FAA for a 767-2C “provisioned freighter” without the aerial refueling components and military avionics planned for the tanker. It will then seek a supplemental type certificate (STC) for a fully equipped KC-46A.

John Howitt, KC-46 deputy program manager, said the two-step certification effort supports Boeing’s strategy of using existing commercial procurement, inventory management and manufacturing processes to build the 767-2C, which will be “provisioned” for the military tanker during fabrication and assembly on the commercial 767 line in Everett, Wash. Mission systems will be installed at a separate facility, a process modeled after Boeing’s “in-line” production of the P-8 Poseidon maritime patrol aircraft, a 737 derivative, for the U.S. and Indian navies. “When we start building the tanker airplane on the commercial line, it will be built from scratch as a tanker,” Howitt told aviation reporters earlier this month.

Boeing is less than a third of the way through the $4.4 billion KC-46 engineering and manufacturing development (EMD) program the USAF awarded the company in February 2011. The EMD contract calls for building four prototype aircraft that will initially serve as a test fleet. The contract also requires Boeing to “maximize the amount of the tanker design that is FAA certified,” Howitt said.

Two of the four EMD aircraft will start flight-testing as 767-2C provisioned freighters to satisfy some basic FAA test requirements, he said. But by the conclusion of the EMD program, all four will be “full-up” KC-46 tankers. Boeing plans to conduct the first flight of the -2C model in the third quarter of 2014, with FAA amended type certification (ATC) following in late 2015 or early 2016. It plans to conduct the first flight of a KC-46 tanker in the first quarter of 2015.

Howitt said the program is “closely coupled on the interdependencies between the ATC and the STC” certifications it seeks from the FAA. “They’re treated as separate projects from an administration standpoint; from a technical standpoint, those people administering the projects are clearly aware of the work statement,” he said. “For example, the -2C will have all the wire bundles installed even though in some cases the radar warning receiver won’t be installed under the ATC. Those certification authorities, the people finding compliance for that wire bundle, need to have some general knowledge of what [we’re] hooking up on the other end.”

Currently, “all eyes are focused” on the program’s critical design review with the USAF, which is scheduled for the third quarter this year, Howitt said. Boeing is halfway through building the first refueling boom, a modernized version of the boom used on the KC-10, which will be used for ground testing. It plans to begin final assembly of the first airframe structure, a wing front spar, on June 26.